Wheel options for my 2018 s3

Hi all,
Got a 2018 S3 sedan on the 18” factory wheels and all season tires .
Thinking in upgrading to the 19” inch wheels and performance tires. Is this something the Audi dealership would do or I would need to go to local shops to do this ?
Another option would be to buy new 18” wheels and replace current ones ( don’t really like the pattern of the factory ones ) but I wonder if that’s a risky or stupid thing to do in a barely new car .
Thanks
James